From: <domi@vi...>  20020328 10:44:05

Well my feeling is that 2*n is enough. I get a good solution for n=10,000 for 20,000 iterations. But it takes very long. Do you think I could try using svd in my case to gain speed? > > whereas for 30 equations it goes banana (wrong solution): > > vnl_lsqr.cxx : The iteration limit ITNLIM was reached. > > vnl_lsqr.cxx : iterations = 30 > > Could you try changing the # iterations to 120 in this case? 60 already gave good results in my case. *I DONT KNOW IF THIS DOESNT DEPEND ON THE MATRIX* I used pretty naive one: for (unsigned i=0; i<n; i++) { A(i,i) = i+1.0; b(i) = i+10.0; } so the solution can be check by head. Domi 